GF/Pb compositeswerefabricated by the method of powder metallurgy, and the density, microstructure and tensile propertywerecharacterized considering the size and content ofglass fibre （GF）. The results show that rel...GF/Pb compositeswerefabricated by the method of powder metallurgy, and the density, microstructure and tensile propertywerecharacterized considering the size and content ofglass fibre （GF）. The results show that relative densities decrease with increasing GF fraction, and the 50μm-GF reinforced specimens exhibit a better densification than the 300μm-GF reinforced ones. The GF particles distribute quite uniformly inPb matrix, and the composites fabricated at low sintering temperature （〈200℃） possess fine-grain microstructure. The addition of GF significantly improves the strength of the Pb composites, and the ultimate tensile strength of the Pb composite reinforcedwith the addition of 50μm-0.5% GF（mass fraction）is about 30MPa higher than that of GF-free sample. For all composites groups, increasing the reinforcement content from 0.5%to 2%（mass fraction）results in a decrease in both tensile strength and ductility.展开更多
Pb?Ag?PbO2 composite anodes with different mass fractions(1%,2%,3%,4%and 5%)ofβ-PbO2 were prepared by powder-pressed(PP)method.The galvanostatic polarization curves,Tafel curves and anodic polarization curves were te...Pb?Ag?PbO2 composite anodes with different mass fractions(1%,2%,3%,4%and 5%)ofβ-PbO2 were prepared by powder-pressed(PP)method.The galvanostatic polarization curves,Tafel curves and anodic polarization curves were tested in sulfuric acid solution.The morphologies and phase compositions of the anodic layers formed after galvanostatic polarization were investigated by using scanning electron microscope(SEM)and X-ray diffractometer(XRD),respectively.The results showed thatβ-PbO2 can improve the electrocatalytic activity of anodic oxide.The anode containing 3%β-PbO2 had the lowest overpotential of oxygen evolution reaction(OER)and the best corrosion resistance.The morphologies of the anode surfaces were gradually transformed from regular crystals to amorphous ones as the content ofβ-PbO2 increased in anodes.展开更多
Hydrogel-Ⅰ was fabricated via sodium alginate in situ-embedding with MAL powders and then applied to decontaminating Pb(Ⅱ) from water. Conditions for preparing Hydrogel-Ⅰ and the adsorption of Pb(Ⅱ) over Hydrogel-...Hydrogel-Ⅰ was fabricated via sodium alginate in situ-embedding with MAL powders and then applied to decontaminating Pb(Ⅱ) from water. Conditions for preparing Hydrogel-Ⅰ and the adsorption of Pb(Ⅱ) over Hydrogel-I were optimized through response surface methodology coupled with central composite design. XPS revealed that the groups of —OH, —COO—, —NH, —NHand —CSS— carried by Hydrogel-Ⅰ were responsible for the uptake of Pb(Ⅱ). Ions exchange, surface complexation, electrostatic attraction and pore-filling effect contributed to the adsorption process. Adsorption performances of Pb(Ⅱ) by Hydrogel-Ⅰ and MAL powders were compared. Although they exhibited similar adsorption rate and maximum adsorption capacity(qm), the reusing ability of Hydrogel-Ⅰ was better and it was easier to be separated from aqueous solution after treatment. Even compared with organic hydrogel materials,Hydrogel-Ⅰ presented relatively quick adsorption speed and high adsorption capacity. It can be concluded that Hydrogel-Ⅰ could be an alternative scavenger for the treatment of Pb(Ⅱ) from aqueous solution.展开更多
文摘GF/Pb compositeswerefabricated by the method of powder metallurgy, and the density, microstructure and tensile propertywerecharacterized considering the size and content ofglass fibre （GF）. The results show that relative densities decrease with increasing GF fraction, and the 50μm-GF reinforced specimens exhibit a better densification than the 300μm-GF reinforced ones. The GF particles distribute quite uniformly inPb matrix, and the composites fabricated at low sintering temperature （〈200℃） possess fine-grain microstructure. The addition of GF significantly improves the strength of the Pb composites, and the ultimate tensile strength of the Pb composite reinforcedwith the addition of 50μm-0.5% GF（mass fraction）is about 30MPa higher than that of GF-free sample. For all composites groups, increasing the reinforcement content from 0.5%to 2%（mass fraction）results in a decrease in both tensile strength and ductility.
基金Project(2017YFB0305401)supported by the National Key R&D Program of ChinaProjects(51874369,51474245,51871249)supported by the National Natural Science Foundation of China+1 种基金Project(2018JJ3659)supported by the Natural Science Foundation of Hunan Province,ChinaProject(2018RS3007)supported by Huxiang Young Talents Plan,China
文摘Pb?Ag?PbO2 composite anodes with different mass fractions(1%,2%,3%,4%and 5%)ofβ-PbO2 were prepared by powder-pressed(PP)method.The galvanostatic polarization curves,Tafel curves and anodic polarization curves were tested in sulfuric acid solution.The morphologies and phase compositions of the anodic layers formed after galvanostatic polarization were investigated by using scanning electron microscope(SEM)and X-ray diffractometer(XRD),respectively.The results showed thatβ-PbO2 can improve the electrocatalytic activity of anodic oxide.The anode containing 3%β-PbO2 had the lowest overpotential of oxygen evolution reaction(OER)and the best corrosion resistance.The morphologies of the anode surfaces were gradually transformed from regular crystals to amorphous ones as the content ofβ-PbO2 increased in anodes.
基金funded by the National Key Research and Development Project (No.2019YFC1804800)Key R&D Program of Shaanxi Province,China (No.2019SF-253)+3 种基金the Fundamental Research Funds for the Central Universities,China (No.300102291504)the Pearl River S&T Nova Program of Guangzhou,China (No.201710010065)the Science and Technology Program of Guangdong Forestry Administration,China (No.2020-KYXM-08)the Key Laboratory of Resource Chemistry,Ministry of Education,China (No.KLRC_ME2102)。
文摘Hydrogel-Ⅰ was fabricated via sodium alginate in situ-embedding with MAL powders and then applied to decontaminating Pb(Ⅱ) from water. Conditions for preparing Hydrogel-Ⅰ and the adsorption of Pb(Ⅱ) over Hydrogel-I were optimized through response surface methodology coupled with central composite design. XPS revealed that the groups of —OH, —COO—, —NH, —NHand —CSS— carried by Hydrogel-Ⅰ were responsible for the uptake of Pb(Ⅱ). Ions exchange, surface complexation, electrostatic attraction and pore-filling effect contributed to the adsorption process. Adsorption performances of Pb(Ⅱ) by Hydrogel-Ⅰ and MAL powders were compared. Although they exhibited similar adsorption rate and maximum adsorption capacity(qm), the reusing ability of Hydrogel-Ⅰ was better and it was easier to be separated from aqueous solution after treatment. Even compared with organic hydrogel materials,Hydrogel-Ⅰ presented relatively quick adsorption speed and high adsorption capacity. It can be concluded that Hydrogel-Ⅰ could be an alternative scavenger for the treatment of Pb(Ⅱ) from aqueous solution.
